The Vertical Conveyer Belt for the Distribution Tower, Programming Loops and Container Ships 

September 18, 2021

Today we checked out some of the items from the CARGO CONNECT Multimedia Resource PDF booklet. Each session has recommended materials all centered around transportation. The short video with a Unique Look inside one of the largest container ships struck a note with everybody. 

Coach Will pausing the video about the Maersk container ship and querying the team what they think about how many containers could fit on that ship. 

Next, we challenged the kids do so some coding on an existing EV3-based robot. We asked what motion the robot could go, and the kids requested the robot to follow a square, going straight, then turn right, and repeat until the robot is returned to the original position.

We picked up the cue and used it as an opportunity for the kids to revisit loops. The program could be two simple blocks. Going straight, turning right, and put a loop of 4 iterations around it.  A challenge arose that the robot has two motors, one for each wheel with a caster wheel at the back. How many rotations does one of the wheels need to complete for a perfect 90-degree angle? The kids decided to take on that challenge by approximating via trial and error.

Coach Will and Coach Bernd could not resist debating how many one-wheel rotations a 90-degree angle requires, could be calculated rather than approximated. However, building a relation between the distance between the two wheels, the diameter of the wheel, and the concept of π was a bit too advanced. We agreed the kids at this stage should simply remember that π exists and that it is something incredibly cool.

The motion of the robot

Leon and Brandon working on the program

Finally, we continued work on our distribution center. We switched from our old conveyer belt (that did not work) to a vertical elevator-style belt. The kids programmed the motor to do enough rotations for the bucket to go up to the right height and come back down. The first iteration worked, but the speed was too high, and cargo wound up flying out of the bucket. A simple decrease in speed fixed the issue and the vertical lifter is deemed a success. The results are not yet consistent with some cargo falling off the distribution tower. A challenge for the next session.

For the next session - Brandon and Will are tasked to improve the platform that catches the cargo. Current design is not delivering consistent results with some cargo falling off the distribution tower. Leon and Bernd are tasked to build a system that moves cargo from the truck onto the bucket of the vertical lift.